1. Field of the Invention
The present invention relates to electronic devices having an energy saving mode to save electric power consumption, and in particular, to a multi-function peripheral having a copy function, a printer function, a facsimile function, and the like.
2. Description of the Related Art
In an electronic device including an image forming unit such as a copying machine, a printer, a facsimile, and the like, an energy saving mode is set through a predetermined operation to suppress the electric power consumption.
Recently, a multifunction peripheral called an MFP (Multifunction Peripheral) having a copy function, a printer function, and a facsimile function is in widespread use. Similar to the copying machine, the printer, the facsimile, and the like, the MFP also generally has the energy saving mode for saving the electric power consumption.
In the energy saving mode of the MFP, a control unit, for example, carries out controls such as turning OFF a backlight of an operation display unit, setting a fixing unit to a preheat temperature, setting a scanner unit to an OFF state, and the like.
The control unit can transition to the energy saving mode based on a transition demand generated when a user operates a predetermined input key, for example.
If a stopped state of each unit of the device is continued beyond a predetermined time, the control unit can transition to the energy saving mode based on a transition demand generated by a timer that measures a duration time.
Furthermore, when a current time and a set predetermined date and time correspond, the control unit can transition to the energy saving mode based on a transition demand generated by a time specifying unit.
A demanding source that generates the transition demand to change to the energy saving mode conventionally includes an electronic device that uses the input key and the time specifying unit, or an electronic device that uses the input key and the timer.
The electronic device does not determine if the demanding source of the transition demand to the energy saving mode is the input key, the timer, or the time specifying unit. Therefore, when accepting the transition demand to the energy saving mode from any one of the input key, the timer, or the time specifying unit, the control unit sets each unit of the device to the energy saving mode.
Thus, if an error state such as paper jam of a paper transporting unit, paper out, toner empty, and the like is occurring when the transition demand to the energy saving mode is accepted, the printing may not be carried out at the time of facsimile reception if the control unit transitions to the energy saving mode without the error state resolved.
Thus, if a predetermined error state such as paper jam of the paper transportation unit, paper out, toner empty, and the like is occurring, the control unit does not transition to the energy saving mode and notifies the error state to the user even if the transition demand to the energy saving mode is made.
In this case, the control unit does not transition to the energy saving mode even if the user cannot resolve the error state that is occurring, and thus an effective electric power saving effect cannot be obtained. For example, when the time specifying unit generates the transition demand to the energy saving mode outside of working hours of an office, the error state remains unresolved if the office is unoccupied, and hence the transition to the energy saving mode cannot be made.